I think my education had a lot to do with it -- not because of what I learned, but how I lived. When I was in prep school, we were not allowed cars, Ditto for most of college. Most of graduate school, I had a car but lack of on-campus parking made it useless for commuting. I was over 30 when I finished school. By then I had a "bikes = trasportation, cars = recreation" mindset. Consequently, bike commuting seemed natural to me and easy to get into.

If I had been a daily "utility motorist" from age 16 on, I suspect that the whole thing would have seemed totally alien. If I lived in an area where driving was more convenient or owned a "beater" car that I did not mind exposing to road salt, body dings, etc., that would have inclined me more to driving. I think commuting choices are strongly multidetermined.

Paul